The FARC had earlier said that it wanted to free Sutay, captured in June near a military base in the remote southern department of Guaviare, as a goodwill gesture, since the rebels and the government are in peace talks to end the five-decade fighting.

"We are not interested in delaying or postponing the handover," said FARC negotiator Ricardo Tellez in Havana, where the talks are taking place.

Colombian President Juan Manuel Santos had refused to allow Piedad Cordoba, a former senator specifically requested by the FARC, to be involved in the release of Sutay, but didn't tell why.

Cordoba has been involved in several previous high-profile FARC hostage releases.

The FARC, the largest guerrilla group in Colombia, described Sutay as a "mercenary" and a "prisoner of war" captured in an "area of fighting" and armed with a secret camera watch, global positioning systems, a military uniform in a gripsack and survival gear.

The United States has said little about Sutay. A short statement from the U.S. Embassy in Colombia confirmed Sutay was a U.S. citizen but "with no current links to the Military Forces of the United States."

The Colombian government, on the other hand, claims Sutay's capture was a "kidnapping" and refused the FARC's offer to release him, saying it "obstructs" the peace talks.

Santos said he would not allow FARC rebels to make a media circus of the release, as they "flagrantly violated" a promise to end kidnappings before peace talks began.

Talks between the two delegations are now in their 12th round, and are centered on the rebels' transition from armed forces to a political movement or party.